Air conditioning terminal

ABSTRACT

An air conditioning terminal for use in an air conditioning system for discharging conditioned air into a space which includes a diffuser spaced from opposed parallel walls; the opposed parallel walls and diffuser cooperate to define therebetween two discharge air streams. Spacers are provided between opposed surfaces of the diffuser and the parallel walls. The sides of the spacers are in intimate contact with the opposed surfaces of the diffuser and parallel walls. The spacer acts to maintain a predetermined distance between the diffuser surface and the opposed terminal wall.

o s" Elite fates ate 1 [m 3 73,?B

Guthei et a1. May B, B973 54] AER CONDITIONING TEHNAL 3,434,668 3/1969Boling ..239 552 [75] Inventors: August W. Gutheim, Chittenango;

Carl 0 Herb, Camillus, both of Primary Examiner-William E. WaynerAttorney-Harry G. Martin, Jr. et a1.

[73] Assignee: Carrier Corporation, Syracuse, NY. 57 ABSTRACT Filed!June 1971 An air conditioning terminal for use in an air condi- [21]Appl No: 156,649 tioning system for discharging conditioned air into aspace which includes a diffuser spaced from opposed parallel walls; theopposed parallel walls and diffuser [52] 11.5.?1. ..98/40 D, 138/108,239/552 cooperate to define therebetween two discharge air [51] int.(,1. ..1F24f 13/06 Streanm spacers are provided between Opposed sub [58]Field Of Search ..l38/i08; 239/552, faces of the diffuser and theparallel walls. The sides 239/590; 98/40 [140C 40 N; 251/153 of thespacers are in intimate contact with the 0pposed surfaces of thediffuser and parallel walls. The [56] References C'ted spacer acts tomaintain a predetermined distance UNITED STATES PATENTS betfiveen thediffuser surface and the opposed terminal wa 3,591,076 7/1971 Bryans..98/4O D 2,828,532 4/l958 Taylor ..239/552 1 Claim, 3 Drawing Figures lIll Patented May 1,1973

l/ 1/ l/ I! 1/ FIG. I

FIG. 3

FIG. 2

INVENTOR. AUGUST W. GUTHEIM BY CARL C. HERB ATTORNEY AIR CONDITIONINGTERMINAL BACKGROUND OF THE INVENTION In air conditioning systemsutilizing ceiling air terminals, a problem is encountered in evenlydistributing the conditioned air throughout the area being served by aterminal. When cool air is being discharged from the terminal, there isa tendency for the air to drop rapidly before there is a completemixture of the conditioned air with the room air. To assure thatconditioned air is provided to the portions of the area farthest fromthe terminal, the air may have to be discharged at a considerablevelocity which can create excessive noise.

A terminal or unit which has proven highly satisfactory in overcomingthe above described problems is disclosed in US. Pat. No. 3,554,111,issued Jan. 12, 1971 in the names of Darwin G. Traver and Fred V.Honnold, Jr. In the above cited patent, it was indicated that the widthof the air discharge slot from the unit is a critical dimension. Inorder to achieve the desired throw" for the air discharged from theunit, it is essential that the width of the slot be maintainedsubstantially constant at a predetermined dimension for its entirelength. The length of such unit may be about 4 feet.

To check the width of the slot for its entire length is both timeconsuming and expensive when manufacturingunits on a mass productionbasis. It is, therefore, an object of this invention to provide an airconditioning unit having a constant width discharge slot that may beproduced in an economical manner when manufacturing such a unit in largequantities.

SUMMARY OF THE INVENTION This invention relates to a ceiling airterminal for use in an air conditioning system to provide treated air toa space within an enclosure. The terminal includes a conduit sectionadapted for connection to a source of conditioned air. Opposed parallelwalls provide an air passage in communication with the conduit section.A diffuser is disposed within the air passage and is held inspaced-apart relation from the opposed parallel walls. The diffuser andparallel walls define therebetween two discharge air slots fordischarging the conditioned air from the terminal into the space beingserved. The width of each of the slots is a highly critical dimension.

Spacers are disposed in fixed positions between the opposed surfaces ofthe diffuser and parallel walls. The sides of each spacer are inintimate contact with a surface of the diffuser and a side wall. Thespacer is designed to maintain noise generation at an absolute minimum.

In a preferred embodiment, the spacer is shaped in the form of ateardrop. The top surface thereof is defined by an arcuate portion. Thesides thereof extend from the arcuate portion and taper inwardly so theyalmost converge at their lower ends. By providing a smooth, rounded topsurface against which the air stream impinges, and by causing the airstream to reconverge at the bottom of the spacer before it is dischargedinto the space, turbulence and thus noise generation is maintained at aminimum.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view of an airterminal embodying the present invention;

FIG. 2 is an enlarged fragmentary view of a portion of the air terminalillustrated in FIG. I; and

FIG. 3 is a frontal elevation of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring more particularly tothe drawings, there is illustrated an air conditioning terminal havingconditioned air supplied thereto. The air is treated in a centralstation (not shown) which may include a filter, precooling coil, spraymeans, cooling coil, heating coil, and a fan, for heating, cooling,humidifying and filtering the air as desired, to provide conditioned airfor passage to the terminals located in the areas being served.

A supply air duct 17 is illustrative of the plurality of ducts providedto supply conditioned air to ceiling air terminals throughout a buildingor other common en closure. The ceiling terminal includes a primarychamber 19 lined with a sound absorbing material 21, such as a glassfiber blanket. The primary chamber is ordinarily open at both ends forconnecting a series of terminals end to end to provide a complete airdischarge system. Suitable end pieces (not shown) are utilized to capthe end terminals in the series.

An air supply distribution plate 23 having a plurality of collaredopenings 25 therein is provided to evenly distribute the supply air fromprimary chamber 19 into the distribution chamber 27 which is defined bythe top and side walls of distribution plate 23. To provide an optimumair discharge pattern, the air supplied to the distribution chamber fromthe primary chamber should have minimal non-vertical velocitycomponents. Since the air supplied to the ceiling terminal is ordinarilyintroduced horizontally into the end or side of the terminal, there is alarge horizontal velocity component to the air stream within the conduitsection. The distribution plate employing a large number of collaredopenings is very effective in providing an efficient, nonturbulentvertical diversion of the air stream from primary chamber 19 intodistribution chamber 27. This minimizes noise generation within theterminal. The collars divert the horizontal velocity component of theair stream so the velocity components of the air stream withindistribution chamber 27 are vertical.

For an optimum air discharge pattern from the plate, the depth of acollar should approximate the diameter of a collared opening. The depthof each collar is constant throughout the entire circumference thereofto provide a discharge opening parallel to the plane of the distributionplate. In discharging air from an opening, the geometry of the openingitself may have a tendency to effect an attachment of the air stream toa portion of the wall forming the opening. This attachment can cause theair stream to be diverted in a direction away from the axis of theopening. By providing a collar having a constant depth throughout itscircumference, an abrupt detachment of the air stream therefrom isobtained which minimizes the tendency of the air stream to flow in anon-vertical direction within the distribution chamber.

The bottom of distribution chamber 27 includes aligned cutoff plates 29which are provided with a curved surface 30 for engagement by bladders31 and 33 to form a damper. The curved surfaces smooth the flow of airthroughout the damper to minimize the pressure drop therethrough whenthe bladder is fully deflated and provide a low noise level over theentire operating range of the terminal as bladder inflation is variedbetween a fully deflated position and a fully inflated position. Thesurface is preferably covered with felt 32 to further minimize noise.

By varying the inflation of the bladders, the area of the openingsbetween the bladders and the cutoff plates may be varied. This featurecan be utilized to provide a variety of modes of terminal operation. lfit is desired to maintain a constant discharge of air from the terminal,a pressure responsive control may be employed to selectively inflate ordeflate the bladders in response to supplied air pressure to reduce thearea between the bladders and cutoff plates as duct pressure increasesand to increase the area therebetween as duct pressure decreases.

If it is desired to control the terminal to provide a constant roomtemperature under varying cooling loads, the bladder inflation may becontrolled by a thermostat responsive to room temperature to provide anincreased quantity of air flow from the terminal as the cooling loadincreases and a decreased quantity of air flow from the terminal as thecooling load decreases.

Bladders 31 and 33 are adhesively mounted on a central partitionassembly comprised of opposed, generally convex plates and diffusertriangle 37. The plates have a suitably-shaped recess therein so thebladders are completely recessed within the plates when deflated. Thisprovides a large area between active walls 34.0f the bladders and thecutoff plates for maximurn air flow therebetween. Further, the recessedbladder provides a smooth surface along plate 35 to minimize airturbulence.

By reference to the drawings, it may be seen walls 34 ofthe bladder areconcave. When the bladders are fully deflated, the active walls of thebladders are withdrawn from theair stream to minimize a possibility ofbladder flutter. By recessing the bladders within plates 35 andproviding the bladders with concave walls 34, the distance between thecutoff plate and wall 34 of the bladders is increased. This provides agreater opening between the bladder and cutoff plate when the bladder isfully deflated for maximum air flow therebetween. Further, a largemovement of wall 34 from a concave to a convex position may be obtainedwithout stretching the bladder material.

The damper mechanism is disposed a substantial distance upstream fromthe discharge openings in the terminal to provide sufficient spacetherebetween to absorb any noise generated by the damper mechanism. Formaximum sound absorption, downwardly extending walls 39 which form airpassages in conjunction,

with plates 35, are lined with a sound absorbing material such as glassfiber blankets Outlet members 41 having outwardly flared lower portions43 are affixed, as by welding, to walls 39.

The convex plates prevent direct, straight line passage of sound energywaves from the damper into the area being conditioned. The sound wavesgenerated at the damper strike sound-absorbing blankets 45 where theyare absorbed to prevent passage of noise from the terminal. The lowerportion of the passageways formed between plates 35 and walls 39 has aconstantly increasing cross-sectional area in the direction of air flowwhich also aids in the dissipation of sound energy.

As noted hereinbefore, for proper air distribution within the area beingserved, the discharged air stream should remain attached to the ceilingduring its passage to portions of the area remote from the terminal.This assures a supply of conditioned air to such remote portions.Another advantage is room air will thus be induced by the discharged airstream and will 'mix therewith to temper the stream so the air streamtemperature is not disproportionate to room temperature, therebyproviding even temperatures throughout the area being conditioned. Theterminal described in the previously cited U.S. Pat. No. 3,554,11 ldiscloses a terminal that satisfactorily discharges the conditioned airinto an area to obtain the results described hereinabove.

As noted in the abovernentioned patent, the width of the air dischargeslot from the terminal is critical throughout its length. The slot isdefined by the opposed surfaces of outlet member 41 and diffuser 37. Itis extremely important that, in order to obtain the desired airdischarge characteristics, the width of the slot be maintained uniformfor the entire length of the terminal, which is typically about fourfeet.

In order to obtain the desired uniformity, spacers are provided betweenthe opposed surfaces of outlet 41 and diffuser 37. v

The front and rear faces, respectively 54, and of each spacer 50 are inintimate Contact with the opposed surfaces of the outlet and diffuser. Ahole 56 is provided in each contacting surface of the diffuser toreceive mating portion 57 of spacer 50. Hole 56 and mating portion 57preferably have a particular configuration so the spacer may only beinserted and thus installed in the air passage in a predeterminedmanner. Joining means 59, such as a bolt and nut, is provided to firmlyaffix the spacer in its desired location within the air passage.

By placing an object, such as spacer 50,'within the flow path of theconditioned air through the terminal, the generation of undesirablenoise may occur. To minimize the generation of such noise, the spacer isformed in a particular manner, as shown in FlG. 3.

The top surface of spacer 50 is defined by arcuate portions 51. Sidewalls 52 and 53 extend downwardly therefrom and gradually taper so as tosubstantially converge at the bottom portion thereof. By providing asmooth rounded top surface for the spacer, noise generation ismaintained at a minimum. In addition, by providing a gradual downstreamtaper the air stream is permitted to reconverge before passing throughthe discharge slot; This reduces turbulence which is a source of noisegeneration. it should be understood that although only one spacer isshown in each air passage, additional spacers may be provided ifrequired.

By providing a spacer of the type described hereinabove, a uniform airdischarge slot may be obtained, without creating any undesirableproblems. Thus, an air terminal may be economically manufactured andstill provide desired characteristics for the air discharged into thearea being served by the terminal.

While we have described and illustrated a preferred space; andembodiment of our invention, out invention should not D. a spacer memberdisposed in a fixed position be limited thereto, but may be otherwiseembodied between opposed surfaces of said diffuser means within thescope of the following claims. and said downwardly extending wall, saidspacer We claim: 5 member being in substantially intimate contact 1. Aceiling air terminal for use in an air conditioning with said opposedsurfaces of said diffuser means and distribution system for dischargingconditioned air a S d nwardly eXtending Wall, Said spacer into a spaceserved by said terminal comprising: member comprising an arcuate portiondefining A. means defining a primary chamber adapted f the upper surfacethereof, and wall means extendconnection to asource of di i d i 10 ingdownwardly from said arcuate portion, said B. at least one downwardlyextending wall associated wan means Substantially converging at thelower ends thereof, said spacer member maintaining a predetermineddistance between said diffuser means and said downwardly extending wallto maintain the width of said air slot uniformly constant at apredetermined dimensionv with said primary chamber to define a firstportion of an air passage;

C. diffuser means held in spaced-apart relation from said downwardlyextending wall to define therebetween an air discharge slot for thepassage of conditioned air from said terminal into said

1. A ceiling air terminal for use in an air conditioning anddistribution system for discharging conditioned air into a space servedby said terminal comprising: A. means defining a primary chamber adaptedfor connection to a source of conditioned air; B. at least onedownwardly extending wall associated with said primary chamber to definea first portion of an air passage; C. diffuser means held inspaced-apart relation from said downwardly extending wall to definetherebetween an air discharge slot for the passage of conditioned airfrom said terminal into said space; and D. a spacer member disposed in afixed position between opposed surfaces of said diffuser means and saiddownwardly extending wall, said spacer member being in substantiallyintimate contact with said opposed surfaces of said diffuser means andsaid downwardly extending wall, said spacer member comprising an arcuateportion defining the upper surface thereof, and wall means extendingdownwardly from said arcuate portion, said wall means substantiallyconverging at the lower ends thereof, said spacer member maintaining apredetermined distance between said diffuser means and said downwardlyextending wall to maintain the width of said air slot uniformly constantat a predetermined dimension.